The present invention relates to a hybrid active array antenna system that includes elements of an electromagnetic spectrum transmitter system and a separate active receive array system. In particular, some embodiments include a system with high power transmission signal, power, and cooling elements at a different location (e.g., an equipment room) separated from an antenna with receive active array elements positioned at a radiating location, e.g., on a mast or tower.
Active arrays with transmit and receive elements require costly high power and cooling infrastructure and provisioning at an antenna location. Existing active array designs with active transmit systems at radiating locations are costly, require higher maintenance, experience increased failure rates due to, among other things, heat generated by transmit amplifiers, and are undesirable particularly in remote locations where maintenance is not easily performed including at mast locations which increase hazards to maintenance personnel.
Generally, embodiments of this disclosure can provide an improved system that reduces need for high voltage and current, cooling, etc. at a radiating location while still improving noise reduction. Embodiments include creating a receive active array system having a low noise amplifier close to each receiving antenna element while having high power transmitter signal generating elements, e.g., comprising an oscillator, high power amplifier, etc. in a separate equipment room which generates an output signal that is passed through a waveguide or transmission line(s) up to an antenna which includes a beamforming network (BFN) that is coupled with antenna radiating elements. Cooling and high power supply system provisioning and routing is simplified as such systems are not required to be routed up an antenna mounting platform or tower. One exemplary hybrid active array can include a transmitter component disposed at a location before the BFN that sets an amplitude distribution of the antenna aperture to control both the transmit and the receive sidelobes. Reducing antenna sidelobes during transmit operations reduces radiation outside of a main beam, further reducing signal returns in the sidelobes, providing a capability not achieved in existing active arrays. Embodiments of the invention reduce complexity and design costs of an array including the antenna design itself
Additional features and advantages of the present invention will become apparent to those skilled in the art upon consideration of the following detailed description of the illustrative embodiment exemplifying the best mode of carrying out the invention as presently perceived.